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Hello 1. Do you know any means, or command, to list all CUI commands that are provided by default in your distro? That will presumably contain 'ls', 'rm', 'cp' and ...so on. I reminded that there are lots of documents in /usr/share/doc directory. So I checked if that should do with what I'm looking for, but there was no any document for 'ls' or 'cp' or whatnot.

2. Who decide what comands are included in distros by default when others not? I check man pages for 'ls', 'rm', 'od', 'paste', so on and it says, the it's core-utiles. It totally makes sense to me. They are essential. However, 'xxd' is installed by default while 'traceroute' isn't. So, in what standard and by whom is this process goes?

3. And, isn't all the GUI command comes with the kernel, right? So, shouldn't every CUI command be the same, right? No...?

4. So, what are these docs from /usr/share/doc for? Are they by any chance only for those packages I installed manually?

2. The Linux Mint developers select what packages are installed by default by the Linux Mint installer. You can suggest additions to the default, using the ideas module on the Community site. Of course you can already install it yourself, and not all programs will be included in the default installer (size constraints both of the ISO image, the download users would have to do, and the needed disk space) so it helps to motivate why something should be included. "I like it" is a bit short Help the developers see why other users (not you) would use this program and for what out of the box usage it should be installed by default instead of being something the users would install themselves.

3. The kernel is just the kernel. Most of the commands you name and refer to are GNU programs, and come from other packages.

4. /usr/share/doc is the place where documents of a package are placed. Like changelogs and readme files. Manpages are in /usr/share/man.